Introduction

For this portfolio I will focus on the album “The Dark Side Of The Moon” by Pink Floyd and the dub version of the album “The Dub Side Of The Moon” by Easy Star All-Stars. Using Spotify’s API’s I will take a look at how Spotify recognizes the differences between these two albums.

The albumcover of The Dark Side Of The Moon is very well known across the whole world. Also the music is critically acclaimed, landing on pace 43 in Rolling Stones’s “500 greatest albums list” (1). Since it was released it has been an inspiration for a lot of artists, especially in progressive rock. The album has innovative elements like spoken-word elements and unconventional time signatures like 7/4 with “Money”.

The reggae re-working of the above-mentioned album has also been very positively received. It is the first album of Easy Star All-Stars. After this the group also made other dub versions of popular album like “Easy Star’s Lonely Hearts Dub Band” and “Ziggy Stardub”. Reggae/dub is known to be happier and more danceable than progressive rock. Also all almost dub/reggae songs are in a 4/4 time signature. It will be interesting to see how Easy Star puts the innovative Pink Floyd album in a dub context.

  1. https://www.rollingstone.com/music/music-lists/500-greatest-albums-of-all-time-156826/public-enemy-it-takes-a-nation-of-millions-to-hold-us-back-2-165804/

Comparing danceability, energy and valence

Valence Dub Side

#### Difference in energy

#### Difference in danceability
#### Difference in Valence

Comparing energy, valence and loudness

*** As you can see there is a very clear difference in energy, valence and danceability between the two albums. Dub Side is a lot more energetic according to the spotify API. Valence is also higher in the dub version of the album, as well as danceability. This is to be expected since the original version of the album is known have a lot of sensitive and calmer music. To make it more dub Easy Star added more instruments and sounds. This makes the music less sensitive and calm but more energetic and positive.

Chromagrams

Any Color You Like - Dark Side

Any Color You Like - Dub Side

Direct comparison in pitch


These two chromagrams show the pitches that are used in this piece of music. I have chosen to compare Any Color You Like with the dub-version of itself. As expected, there is not a lot of difference between the two. The dub-version still plays the same notes, otherwise it would be a different song. However, the dub-version is a bit longer (3:38) than the original (3:26).

In the last graph we can see a direct comparison of the two versions. there is no diagonal blue line like with a self similarity matrix, because it is not an exact copy. Since there are no recognizable shapes in the graph we can conclude that the two songs are symmetrical in song-structure. According to the color of the graph there is some difference in pitches but not a lot. This is all very logical.

Ceptograms

The Great Gig In The Sky - Dub Side

The Great Gig In The Sky - Dark Side

*** I have made cepstrograms of the two versions for The Great Gig In The Sky. The Dark Side version has a very clear magnitude on c02. This is because of the singing of Clare Torry which gives a boost in the energy levels and a very different timbre to the song. The dub version also has its highest magnitude on c02 but it is not as strong as the Dark Side version. This is because the singing is not in the foreground but it makes place for Easy Star to show how to dub!

Timbre self similarity matrices

The Great Gig In The Sky - Dub Side

#### The Great Gig In The Sky - Dark Side

*** In the two self similarity matrices show that the timbre of the dub-version stays the same for the whole song. The original version however, does have some differences. It is also clear that Clare Torry starts to show her vocal virtuosity around 75 seconds. After the first 2 blocks it gets a bit messy because it is part instrumental and part vocal. However, there is still somewhat of a checkerboard recognizable which indicates the song is very homogene.

The graph of the dub-version is very empty and there is no recognizable pattern. This means that there a no changes in timbre in the song.

Chordograms

Money - Dub Side

Money - Dark Side


The parts between around 30-150 seconds and 300-350 seconds of the Dark-version seem very identical which also corresponds with the actual song. according to Wikipedia the song is the key B minor, which we don’t see in chordogram (2). E-flat major seems to be the strongest chord according to our chordogram, so that’s very interesting. It looks like the chordogram finds it difficult to follow the chord-progression of the song.

It looks like there is less going on in the Dub-version. I think this is because the solo of the Dark-version (which contains the two clear peaks) is replaced by Jamaican-like singing about Jah and money. Also there is a lot of echoing used which might influence how spotify sees the chord-progression of the song

  1. https://en.wikipedia.org/wiki/Money_(Pink_Floyd_song)

Tempograms

Time - Dub Side

Time - Dark Side

Standard deviation tempo comparison


It appears to be hard for the code to determine a clear BPM for the song. Both songs start with clock alarms (the dub-version contains somewhat more primitive alarms like the sound of a rooster) which explains the start of both tempograms. When the singing starts around 150 seconds the BPM rises from 120 to 130. around 180 seconds the song gets more calm and background vocals are added. Apparently this makes it very difficult for spotify to observe a tempo. between 300-330 seconds the music repeats like it was around the 150 sec mark. Also the more calm bit gets repeated.

The Dub-version is a lot more clear. Because of the reggae rhythm it is easier for spotify to find a clear tempo. This version doesn’t have a calmer bit with background vocals. We still see the same change in tempo around the 150 second-mark, which is when the singing starts. The tempogram also gets confused around the 350 seconds. This is when almost all music fades out.

The last graph shows us that Dark Side has a lot more variance in tempo. My theory is that all of the music by Pink Floyd is harder to put into a clear tempogram because of the way that the music is composed. Also, in dub music there is not a lot of variance in tempo.

Dendrograms

Dendrogram Dark Side

Dendrogram Dub Side

*** The dendrograms show that is hard to put the songs into clusters. I must admit that I find these graphs confusing for this project since the all the songs are from the same album and thus are somewhat alike. Therefore it is a bit pointless to see what clusters are formed. However it is interesting to see that most songs are separate from eachother.

Conclusion

So, what did we learn from all these graphs and analysis?

First we saw that there is a very clear difference in danceablity, valence and energy between these two albums. This is what we expected because reggae/dub is known to be danceable and happy music. Also, the Pink Floyd album is very beautiful but it is not danceable!

In the chromagrams we learned that the same notes are used in both versions of Any Color You Like. This is very logical because it is mostly the same song. Also the song structure remained the same in the dub-ified version.

In the cepstrograms we saw that the singing part in The Great Gig In The Sky really showed in the original version while it wasn’t clearly visible in the reggae version. This is because the singing wasn’t in the limelight of the song but the reggae-riddim was.

In the self similarity matrices of the same song we still see the parts where the singing is happening. In the dub version we don’t see any shapes which tells us that there are no changes in the instrumentation of the song.

The chordograms showed us that it is difficult to find the chord progression of the songs. It seems like the chords are blurry because of the overtones of the notes that are played. We can still see a difference between the two versions of Money and we can explain this because of the different song-structure. The dub version has a lot of singing in the part where there is a solo in the normal version.

The tempograms of Time were also hard to determine for the algorithm. But there was a clear similarity between the two versions in tempo. This is also explainable because it is stil somewhat the same song.

We also saw that Dark Side Of The Moon has a lot more variance in tempo. I think that has to do with the algorithm struggling with determining a BPM when the songs are a bit more soft.

At last we had the dendrograms clustering the songs. Here we saw that almost all songs of both albums got separated from eachother.

I found it to be very interesting to see how spotify sees the difference between these two albums. The albums are very similar but also very different. Mostly the timbre is different and the pitch is the same. Which is to be expected with different versions of the same song.